The link above will take you to the blog of one Cody Brocious, who heads up this project. It's goals are to create a wrapper for Windows executables that will allow (among other things) DirectX 10 graphics to run on Intel Macs, Linux and, most importantly, Windows XP. If they do indeed succeed, Microsoft's strategy to entice upgrades to Vista by not allowing the newest games to run on XP is in at least some danger.
If Cody has indeed reverse-engineered DirectX 10's Geometry Shader (probably the key component) it is a great accomplishment. They have formed a company, I guess to monetize the work. You can view their site here.
It's an interesting project. We will have to see how they do.